"Just when you think it can’t get worse with this administration, it does," Christie said.

He said that he would have taken stronger and swifter action against Russia in Ukraine and Eastern Europe, and he would immediately set up no-fly zones in Syria to protect U.S. allies there.

"The fact is, this president has chosen inaction over action," Christie said. "Every place around the world, he pulls America back, he retreats and he apologizes. And that's not who America is. That's not who the American people are. And they're tired of this president."

Christie said that Russian President Vladimir Putin is "swinging above his weight" because his country's economy is in the tank, and the only American he can actually knock out is Obama.